Sony decks are typically a good match for Z's due to their sensitive tuners. I have a few plug and play "Sony to Z32" harnesses left, I believe.
The first thing I'd do is check and see if the car still has the original Bose enclosures. If so, the best / simplest option would be exact fit JBL speakers for them. You can also use high impedance Bose drivers, but they won't sound that great without tweeters / biamplification.
If by chance your car still has the four original enclosures, you really only need the following pieces:
deck
dash harness
speaker harnesses
replacement speakers
If you find no enclosures to work with, then you'll have to make some other decisions...based on cost, sound quality, installation time, etc.
If you have any more questions, email me directly. I still check that at least two or three times a week:
zmaxsystems@musfiber.com
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